GPS over Fibre

GPS Point-to-Point Optical Fibre Link

GPS over Fibre technology can be used to extend the range of a GPS antenna feeder cable well beyond what is achievable by use of coaxial cables.

Signal losses through attenuation limit the range of a coaxial cable-based system to perhaps a few hundred metres when using low-loss cable and amplifiers, whereas an optical fibre system has a reach of several kilometres by comparison.

A typical point-to-point optical link consists of three main components:

An optical transmit (TX) module

A length of single-mode optical fibre cable

An optical receive (RX) module

The transmit module converts RF signals from the outdoor antenna into light pulses and transmits them down the optical fibre link.

The receiver at the far end converts the light pulses back into RF signals and passes them to the GPS equipment (repeater | receiver | timing module).

Key features:

The transmit module provides a DC voltage to the low noise amplifier (LNA) in the GPS antenna

The receive module terminates the DC voltage output from the GPS repeater/receiver and presents an impedance that simulates the presence of a GPS antenna

Standard optical connector type is SC/APC (FC/APC on request)

Power for each unit is via the DB9 connector and an external +12V power adapter